Download the tar.gz package from https://dotnet.microsoft.com/download/dotnet
and install the package with this command:
mkdir -p $HOME/dotnet && tar zxf dotnet-sdk-6.0.100-preview.3.21202.5-linux-x64.tar.gz -C $HOME/dotnet
export DOTNET_ROOT=$HOME/dotnet
export PATH=$PATH:$HOME/dotnet
the scound version will be added to sdks folder and you can confirm the installation by running:
dotnet --list-sdks
I have found all the other solutions useless and hard to utilize and dotnet-install script is just very hard to use and pointless.